1. The Field of the Invention
The present invention is directed generally to a portable railcar sill step extender. More specifically, the present invention is directed to a portable railcar sill step extender that is adaptable to a damaged or undamaged railcar sill step.
2. Background Art
A railcar is a railway vehicle that is adapted to travel on the rails of a railway and is largely used for hauling materials. Railcars are typically coupled together to form a train and are hauled by a locomotive. In placing railcars at destinations or a rail yard such that their contents can be unloaded or new contents loaded, in order to avoid having to walk distances, rail workers typically ride onboard railcars by standing on a sill step and clinging onto one or more handholds disposed above the sill step. Sill steps are typically mounted on the sides of a railcar and near each corner of the railcar and provided as steps for placing ones' feet at a height between the lowest handhold and the ground. A sill step is typically constructed in the form of a U-shaped structure from substantially flat metal stock. The handholds are provided for an operator to grip while ascending or descending a sill step. A rail worker may stand on a sill step and hold onto a handhold of a railcar as the railcar is transported around a rail yard. A sill step is typically mounted inward of a railcar, i.e., between side walls of the railcar so as to avoid protruding into objects disposed along the travel path of the railcar. Consequently, the rail worker must lean outward at an angle, making for an uncomfortable and non-ergonomic posture. Attempts have been previously made to alleviate these problems.
U.S. Pat. No. 7,849,962 and U.S. Pat. No. 7,828,118 (hereinafter Barbara) disclose a rail vehicle step configured to be mounted to a sill step of a rail vehicle in an attempt to solve such problems. In Barbara, a support is sized and adapted to a sill step to support a rail worker. A coupling is sized and configured to hold the support in fixed relation to the sill step. The support is sized to extend outward beyond the side walls of a rail vehicle and support a rail worker. Various disadvantages are associated with Barbara's support.
Barbara discloses a clamp type securing means that is complex. The securing means includes a screw (100 of Barbara) and ratchet structure (104 of Barbara) and causes unnecessary hauling of extra weights while not enabling positive locking of Barbara's step to the sill step of a railcar. The capability of positively locking a support onto a sill step is especially important considering the vibration that can potentially dislodge the securement of Barbara's support placed on the sill step. In addition, the contact surface of Barbara's screw (100 of Barbara) and a sill step is minimal at best. It is also difficult to realize when Barbara's support is sufficiently secured to a sill step as Barbara's screw may be made of materials of similar hardness to a sill step and therefore lacking the deformation in at least one of the two parts to generate sufficient grip to prevent relative motion between the two parts. Further, Barbara's step is incapable of being adapted to deformed sill steps of railcars to result in a leveled support for a rail worker as Barbara's support is only capable of forming a support having a stepped on surface that is substantially parallel with the sill step to which it is attached.
Thus, there arises a need for a portable railcar sill step extender that is capable of being positively secured onto both undamaged and deformed sill steps without unnecessary adjustments and alignments.